Electronic mail service system and method that make use of dynamic IP filtering technology

An e-mail service system including a dynamic Internet protocol filtering module and interconnected to a plurality of remote servers via a communication network, each one of said remote servers including a mail transfer agent, said e-mail service system comprising:

• means for receiving a connection request to the plurality of remote servers from a remote host;
• means for extracting an Internet protocol address corresponding to the requesting remote host according to an Internet protocol block;
• means for determining permission of connection by comparing a predetermined reference value with a summation value of the number of past requests made during a predetermined control time period and current request from the extracted Internet protocol address, the predetermined control time period is divided into a number of slices;
• said dynamic Internet protocol filtering module including means for resetting, before the determination of connection permission, a connection request number in a slice between previous connection time and current time;
• and
• means for transferring to a corresponding remote server an e-mail to which a connection is permitted by the determination means.

In an e-mail service system, a method for dynamically filtering an Internet protocol address comprising the steps of:

• receiving a connection request from a remote host;
• searching an Internet protocol block and extracting an Internet protocol address corresponding to the requesting remote host from the Internet protocol block;
• determining a connection permission by comparing a predetermined reference value with a summation value of the number of past requests made during a predetermined control time period and current request from the extracted Internet protocol address, the predetermined control time period is divided into a number of slices;
• and
• resetting, before the determination step, a connection request number in a slice between previous connection time and current time.

In an e-mail service system connected to a plurality of remote servers, each one of the plurality of remote servers including a separate mail transfer agent, a method for dynamically filtering an Internet protocol address comprising the steps of:

• receiving a connection request to the plurality of remote servers from a remote host;
• searching an Internet protocol block and extracting an Internet protocol address corresponding to the requesting remote host from the Internet protocol block;
• determining a connection permission by comparing a predetermined reference value with a summation value of the number of past requests made during a predetermined control time period and current request from the extracted Internet protocol address, the predetermined control time period is divided into a number of slices;
• resetting, before the determination step, a connection request number in a slice between previous connection time and current time;
• and
• transferring an e-mail associated with the remote host to which the connection is permitted at the step of determination to the corresponding remote server.

A method, comprising:

• receiving a connection request from a remote host;
• determining an Internet protocol address corresponding to the requesting remote host;
• resetting a number of connection requests in slices between a previous connection time and a current connection time;
• and
• determining a connection permission by comparing a predetermined reference value with a summation value of the number of past requests made during a predetermined control time period and current request from the determined Internet protocol address, the predetermined control time period being divided into a number of slices.